The interest of this molecule has been greatly enhanced in the recent years due to the increased incidence of infections caused by organisms producing extended-spectrum beta-lactamases (ESBL), making it to become a sparing-drug for carbapenems.8-10 Temocillin presents MICs ranging from 2 to 32 mg/L against Enterobacteriaceae, including most ESBL producers.1,2 Like all beta-lactam antibiotics, the time above MIC for free drug concentrations (ƒT>MIC) is the important PK-PD parameter correlating with its efficacy.11 When the beta-lactam antibiotic concentrations do not exceed the MIC for 40% to 50% of the dosing interval, the efficacy of a beta-lactam antibiotic can be compromised. When a cut-off of a ƒT>MIC of 40% is used, a Monte-Carlo simulation of the available data defines a clinical PK/PD breakpoint of 8 to 16 mg/L for temocillin.11-13 The available temocillin pharmacokinetics data (distribution, metabolism, and elimination) comes from studies performed in adults. It is mainly excreted unchanged (80%) in the urine by glomerular filtration and tubular secretion.3